Conventionally, personal computers are equipped with pointing devices as peripheral device for enabling input of coordinate data, selection of a menu, moving of an object, and so forth. The typical pointing device may include a mouse, touch pad, track point, track ball, and pointing stick. The mouse is widely used in desktop computers for its fine sensitivity and resolution. Instead of the mouse, a track ball, track point, and touch pad have been used in portable computers such as a notebook computer for their compactness fit for the smaller size of the portable computer. The pointing devices are incorporated into the main body of the notebook computer to perform corresponding mouse function. Buttons are provided on the surface of the main body to be pressed or clicked manually and to control certain functions that may be customized to suit the user.
However, it is common to users of the notebook computers that the use of the track ball or touch pad is inconvenient and less precise compared with the mouse. Particularly, it is difficult for a novice to locate a pointer at fine position on screen, since movement of the pointer made by a finger is instable. To control movement of the mouse pointer precisely in the notebook computer, either changing the mouse resolution to higher one or adjusting the mouse pointer speed slowly is needed. The adjustment of the pointer speed should be performed through the corresponding control program each time it is required to fit for the use. Change of the mouse resolution as well as adjustment of the mouse operation is troublesome and time consuming.
U.S. Pat. No. 5,565,888 for a Method And Apparatus For Improving Visibility And Selectability Of Icons to Selker discloses a display enhancement scheme that expands the size and the selection zone of icons when a pointer falls within a vicinity of the icon. This arrangement for enlarging the size of the icons is automatic and does not require the user to press a button or use a complicated display menu to enlarge the size of the icons. The enlargement of the icons is out of the control of the user as the user is not required to press any buttons to cause the icon to become enlarged. U.S. Pat. No. 5,187,776 for an Image Editor Zoom Function to Yanker discloses a user controlled ZOOM function that enlarges the region of the screen surrounding the cursor. Yanker requires the user to depress CNTR-Z to activate the ZOOM function and the ESC key to deactivate the ZOOM function. Yanker uses an image editor to activate and deactivate the ZOOM function. What is needed is an arrangement where the user can enlarge the screen in the vacinity of the pointer. What is also needed is a single key that both activates and deactivates the ZOOM function. Finally, what is needed is the above to be carried out without the use of an image editor.